1. Field of the Invention
The present invention relates to a configuration of a game ball. The invention concerns, more particularly, a game ball that includes bridged, non-equilateral, hexagonal panels.
2. Description of Background Art
The soccer ball, also referred to as a football or foosball, is the primary piece of equipment used in the game of soccer. The traditional soccer ball conventionally includes a paneled casing that surrounds an inflatable bladder. The casing is formed of a plurality of durable, wear-resistant panels that are stitched together along abutting edges to form a closed surface. The bladder, located on the interior of the casing, is formed of a material that is substantially impermeable to air and includes a valved opening, accessible through the casing, to facilitate inflation of the bladder. When inflated, the bladder expands and places a uniform outward pressure on the casing, thereby inducing the casing to take a substantially spherical shape, but not a perfectly spherical shape. Some traditional soccer balls may include a lining between the bladder and casing to provide protection for the bladder.
In mathematical terms, the panels that form the casing of the traditional soccer ball correspond to the various faces of a regular, truncated icosahedron. An icosahedron is a polyhedron having twenty faces. The term regular, when applied to an icosahedron, denotes a configuration wherein each of the twenty faces is an equally-dimensioned, equilateral triangle. A regular icosahedron, therefore, includes twenty equilateral triangular faces and twelve vertices that are formed where points of five triangular faces meet. A regular, truncated icosahedron is a regular icosahedron, as described, wherein each of the twelve vertices are removed, thereby converting the vertices into twelve pentagonal faces and converting each triangular face into a hexagonal face. Accordingly, a regular, truncated icosahedron is a polyhedron having thirty-two faces, twelve of which are equilateral pentagons and twenty of which are equilateral hexagons, and sixty vertices formed where the points of three faces meet.
The traditional soccer ball casing, which is modeled on the regular, truncated icosahedron, therefore includes thirty-two panels composed of twenty equilateral hexagonal panels and twelve equilateral pentagonal panels. The panels are stitched together along abutting edges, the stitches being located on the interior portion of the casing. The internal pressure imparted by the bladder causes each panel of the traditional soccer ball to bow outward, thereby inducing a substantially, but not perfectly, spherical shape in the soccer ball.
U.S. Pat. No. 5,674,149 to Schaper et al., hereby incorporated by reference, describes certain limitations of the traditional soccer ball. In particular, it is noted that when the soccer ball is inflated, the hexagonal panels experience greater stresses than the pentagonal panels. In addition, the degree of stress in the seams that join two hexagonal panels with each other is greater than the degree of stress in other seams. The Schaper patent further describes the increased rate of wear brought about by the stress differences described above. In particular, the seams between the hexagonal panels wear more quickly than other seams, and the hexagonal panels themselves tend to wear more quickly than the pentagonal panels.
The Schaper patent attributes these limitations to the specific configuration of the panels that comprise the traditional soccer ball. When the bladder is inflated, the bladder contacts the hexagonal panels prior to contacting the pentagonal panels. When the bladder contacts the pentagonal panels, therefore, the bladder is already in contact with a relatively large surface area of the hexagonal panels. The disparity in the manner in which the bladder contacts the panels contributes to the stress and wear differentials described above.
In order to provide a soccer ball that overcomes the limitations of the traditional soccer ball, the Shaper patent discloses a soccer ball configuration wherein the hexagonal panels and the pentagonal panels are subjected to essentially equal material stresses and degrees of stretch and whose spherical shape is improved. More specifically, the soccer ball disclosed in the Schaper patent includes a casing with equilateral pentagonal panels, and with non-equilateral hexagonal panels. Each hexagonal panel includes, therefore, both short edges and long edges. According to the Schaper patent, the ratio of the length of the short edges to the length of the long edges is preferably 0.839. The hexagonal panels are then arranged such that the long edges abut the long edges of other hexagonal panels, while the short edges abut the edges of pentagonal panels. In addition to reducing stresses, an advantage of the configuration wherein the hexagonal panels include both short and long edges is that the spherical characteristics of the soccer ball are improved in comparison with traditional soccer balls.
The Schaper patent, in summary, advances the concept that differences in stress in seams that join the hexagonal panels, differences stress between the hexagonal and pentagonal panels, and differences in wear may be alleviated by utilizing hexagonal panels that are both equiangular and non-equilateral. A further advantage of this configuration is that the spherical shape of the soccer ball is improved, thereby reducing the number of soccer balls that are rejected during the manufacturing process because they do not meet specific tolerances regarding roundness, weight, and center of gravity. The present invention provides a soccer ball that is even more spherical than the soccer ball disclosed in the Schaper patent, thereby providing a further reduction in the number of soccer balls that are rejected during the manufacturing process.